Self-launching aeroplane.



. N. u. FROST.

' SELF LAUNCHING AERQPLAN E.

APPLICATION FILED OCT-16' I917;

- Patented 11111.29, 1918;

NORRIS H. FROST, OF WEST HOBOKEN', NEW JERSEY.

snnr-raunonme AEROPLANE.

Specification of Letters Patent.

Patented Jan. 29,- 19 18..

Application filed October 16, 1917. serial No. 196,811.

forming a part of the aeroplane to facilitate the launching of thelatter, the launching force being primarily the tractive power or thepropelling force of the engine driven propeller of the aeroplane.

In the present method of launchin aeroplanes, it isordinarily necessaryto iave a considerable area of evenly prepared surface over which thewheels of the chassis may run until the required momentum has beenreached to enable the operator to raise the machine from the earth. Ithas also been proposedto'have special launching devices whichWilli-project the aeroplane by energy stored in or applied through suchlaunching device. These methods of launchingv operate successfully atthe home station or base, but it is often necessary for the aviator toland in a locality where the desired charthe aeroplane itself with anattachment so constructed that the aeroplane may be raised into the airand launched without the necessity of traveling along the ground for anyappreciable distance. Furthermore, the

energy required for lifting the aeroplane I derive entirely from themotor of the aeroplane and insure high speed of the motor with theresulting high tractive or propelling force of the propeller before theaeroplane has traveled a distance equal'to its own length, whereby theaeroplane may very rapidly acquire high speed.

l/Vith my im roved construction the aviator can launchflhe aeroplanefrom localities Where the conditions are such that launching in theordinary vmanner is difficult if not impossible. x In the accompanyingdrawings to Wh1ch portin acte'ristics of the ground are lacking, as forreference is to be had, I have illustrated one embodiment of myinvention but I desire that this embodiment be considered in anillustrative rather than in a limiting sense as various changes may bemade Within the scope of my invention as described in the appendedclaims. In said drawings,

Figure 1 is a front elevation of the aeroplane at the instant of takingflight;

Fig. 2 is a side elevation showing the parts in solid lines in positionpreparatory to launching and showing in dotted lines the parts at theinstant of launching; and

Figs. 3 and 4 are views of minor details-of construction. v I

I have shown my invention as applied to a biplane of the tractor type,the aeroplane having a fuselage 10, a pair of superposed planes 11 and12, a propeller 13 and Wheels 14 facilitating. the movement of theaeroplane along the ground. This aeroplane,

so far as the main features thereof are concerned, forms no portion ofmy invention and is only diagrammatically illustrated.

My invention is equally applicable to machines having the propeller orpropellers at the rear rather than at the front and provided with asingle or more than two supplanes. To acilitate the launching, Iprovide'a frame 15 pivoted to the body or other rigid part of themachine adjacent to the front end thereof and adapted to lie in adownwardly and forwardly inclined position with the front end restingupon the ground when the aviator is ready to launch the machine. Thisframe may vary in character, in point of attachment to the. aeroplaneand in details of construction. in accordance with the from tiltingsidewise during the launching operation.

When the aviator desires to launch the machine, this frame is brought tothe position illustrated in solid lines in Fig. 2 and the front lowerend'of the frame which rests on the ground is so braced or anchored thatit cannot push forwardly along the ground.

' details of construction of the frame.

As the aeroplane one is started, the frame will at first prevent anyforward movement of the aeroplane and willofier such a resistance thatthe engine may speed up until speed and the speed of the aeroplaneitself will increase to such an extent that when the parts'reach theposition shown in dotted lines in Fig. 2, the aeroplane and its engineand propeller will have such speed that the aeroplane may continue itsforward movement without any material lowering of the body as the frameswings rearwardly.

After the aeroplane is thus launched, the frame may be disposed of bythe aviator in various different ways, depending upon the method ofattachment of the frame and $118 or instance, it may be pulled back tothe forwardly extending position preparatory to its use at the nextlaunching or may be formed of telescoping or folding sections which maybe unlocked upon the pulling of levers or cords and the frame brought toa folded position. As illustrated, the two arms are mounted to swing notonly forwardly and rearwardly, but also may swing laterally to bring thelower ends of the arms closely together or along the sides of thefuselage during flight. shown one of these arms 16 with a collar 18turning on a transversely extending pivot 19 carried by the fuselage andclosely adjacent to this collar is a pivotal connection 20 about whichthe arm may swing transversely of the machine.

The transverse brace 17 between the arms is shown in Fig. 4 as having ahinge 21 intermediate of its ends so that it may either hold the armsspread apart to the desired distance or the hinge may bend in bringingthe arms together. The ends of the brace 17 will of course be hinged tothe arms. cord or wire 22 is shown as being connected to this brace 17and extending over a pulley 23 so that after the aeroplane is launched,the aviator may pull on the cord and thus both bend the brace17,-bringing the arms together, and lift the arms to a position alongand beneath the fuselage as shown in dotted lines inFig. 2.

By the use of only a single frame, the front end of the aeroplane willbe raised while the lower end advances along the ground until theaeroplane takes flight. This will give the machine a decided tilt InFig. 3, T have hea set) which willv facilitate the upward movement ofthe aeroplane and the speedy launching.

I may, if desired, and in some constructions do, preferably employ asecond and somewhat similar frame at the rear end of the machine so thatthe body will swing upwardly in parallelism or by making the rear frameshorter than the front one, the entire machine will rise but with thefront end to a greater extent thanthe rear end. I have illustrated aframe 24 pivotally connected to the rear end of the fuselage and similarin all respects to the frame above described except that it is shorterand does-not raise the rear end of the machine to as great an extent asthe front end during the launching operation. This frame is shown asprovided with a cord or wire 25 extending over a pulley 26 so that theaviator may pull the frame up to a forwardly extending position beneathor alon the body instead of a rearwardly exten in positlon as is thecase of the front frame illustrated.

After the aviator lands, he may lower the rear frame to the positionshown in solid lines in Fig. 2 and may move the front frame to itsforwardly extending position in various difi'erent ways, depending uponthe details of construction of the latter. For instance, he may removethe pivot pins which connect the front arms 16 to the body, therebyentirely detaching the frame from the body and then move it around tothe desired downwardly and forwardly extendin position and replace thepivot pins.

Tt will of course be evident that the fou. front ends of the arms whichare illustrated as being comparatively sharp, due to the small scaleupon which they are illustrated, may be made in any suitable manner toprevent them from penetrating into the ground to any material extenteven though the ground he comparatively soft.

In case the tractive or propelling force is above described,particularly where the ma- .chine is a very heavy or heavily loaded one,

additional force may be brought to bear to efiect the desired relativemovement of the frame or frames and the body of the aeroplane. Forinstance, a very heavy spring may be put under tension by any suitablemechanism on the aeroplane and this spring may be released when theengine is started and may act on the frame or frames and the bodyto-tend to produce the relative swingmg movement of the frame from theposition shown in solid lines in Fig. 2 to the vertlcal position shownin dotted lines. The details of such a spring are relatively unim:portant and T have not illustrated such details. T have merely shownrather diagrammatically a pair of heavy coil springs 27 carried by thebody and acting upon the arms 16 at a short distance in front of thepivotal 13o masses connections between the latter and the body. Thesesprings ma have an suitable means at their upper en 5' and wit in thebody for placing them under high compression. Af-

' ter the machine is launched, they may be drawn back up into the bodyand again compressed ready for the next launching.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. An aeroplane having a pair of frames pivotally secured thereto, oneadjacent to the front end and the other adjacent to the rear end, eachof said frames having their front lower ends adapted to rest upon theground and swing about said lower front ends to raise the aeroplane whenthe tractive or propelling effect of the aeroplane pro peller acquiressuflicient force to raise the aeroplane, the front frame being of eaterlength than the-rear frame, where y the front end of the aeroplane israised to a greater extent than the rear end during the launching, I

2, In combination, an aeroplane, a pair of frames of difl'erent lengths,the longer frame having pivotal connectionsv with the aeroplane adjacentthe front end of the latter and the shorter frame having pivotalconnections with the aeroplane adjacent to the rear end of the latter,said frames occupying downwardly and forwardly extending positions andhaving their lower front ends held against forward movement during thelaunchmg to insure the upward and forward movement of the aeroplane assaid frames swing about their lower ends as pivots with the front end ofthe aeroplane rising to a greater distance than the rear end.

Signed at West Hoboken, in the county of Hudson and State of New Jerseythis 10th day of October, A. .D. 1917.

NORRIS H. FROST.

